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Tell the Truth, and Live Longer. (No Lie!)

Want to live a longer healthier life? Chill out. And stop lying. For the same reason. Stress is really REALLY bad for your health.

Chronic stress is bad for your health in a lot of ways. (“Chronic” means the kind you don’t get used to – like the hassles of daily commuting – and the kind that bothers you for longer than a couple weeks.) Biochemically, stress means you are in a mini-Fight or Flight mode, and the bodily systems you need to protect yourself are turned up while the systems you don’t need are turned down. That’s fine in the short term, but those systems aren’t designed to STAY turned up or turned down, and if they do, things get out of whack in harmful ways. Elevated blood pressure contributes to cardiovascular damage. Depressed immune function makes you more vulnerable to infectious disease. Higher than normal levels of stress impair long-term memory, fertility, bone formation, the health of your digestive system, and dramatically increase the likelihood of adult onset (Type 2) diabetes and clinical depression. (For much more on this, read the delightful Why Zebras Don’t Get Ulcers by Robert Sapolsky.)

But stress eats away at us in an even more insidious way, a frighteningly literal way. The ends of our chromosomes (coiled sections of DNA that contain several genes, each cell has 23 pairs) are made of sections called telomeres. These telomere ‘caps’ keep the chromosomes from unraveling at their ends and separate one chromosome from another. (A common analogy for telomeres is the plastic caps on the ends of shoelaces.) As cells divide, those pairs of chromosomes split up. One strand of each chromosome goes off to the new daughter cell, while another stays home in the parent cell. Each cell then makes a new copy of each single chromosome strand it has, which pairs back up with the strand from the original set. Telomeres form to cap the ends of these new pairs. But each time this happens the telomeres get shorter, and when the telomeres are gone, the cell dies. This is aging down at the cellular level, and quite natural. But unless you want to live a shorter life, it’s not a process you want to speed up. Stress does.

A 2004 study of 20 – 50 year-old mothers, half with healthy kids and half with chronically ill children, found that the moms of the sick kids had significantly shorter telomeres than the moms of healthy kids. The subjects also filled out a questionnaire about how stressed they felt, and the moms who perceived more stress – whether they had healthy kids or chronically sick ones – had shorter telomeres than the moms who did not feel as stressed. The most stressed moms’ telomeres were so much shorter that, in effect, their cells were 10 years older than moms of similar age who didn’t feel stressed!

The damage is believed to be cause by higher levels of stress hormones, glucocorticoids, in the moms who perceived their lives as more stressful. But what’s important here is that it was how stressed the moms felt that mattered, not the reality of having to take care of chronically ill kids. Moms with sick kids who didn’t feel stressed, no matter how stressful their lives might seem, did not suffer as much of this damage.

So, in the name of your own health and longevity, chill! And one way to do that is to stop lying. When you lie, and you are subconscious or consciously afraid you'll get caught, it creates stress. Lie detectors depend on this. They work by sensing the changes in skin electricity and pulse and breathing rate, even the pitch of your voice from slightly tightened vocal cords, produced by the chemical reactions you’re undergoing when you’re stressed. (Glucocorticoids are the triggering hormones behind these reactions.)

Anita Kelly and LiJuan Wang of Notre Dame recruited a group of 110 people from 18 to 71 years old, and told them that once a week for ten weeks they’d have to come in and, in a lie detector machine, report how many times in the previous week they had lied. But the group was divided in half. 55 of them got explicit instructions in how to avoid lying. (They could avoid telling the truth, or not answer, just not out and out confabulate.) The other group got no instructions, just the request to come in once a week and tell the truth about how many times they had lied last week.

Everybody lied less. But the group that had gotten advice on how to avoid lying reduced their fabrications far more. And in questionnaires, those who had lied less reported better mental and physical health. They reported improvements in their relationships, less trouble sleeping, less tension, fewer headaches, and fewer sore throats. (The results haven’t been published yet. They were reported at a professional meeting.)

The authors and their psychologist colleagues explain this behaviorally. They say this proves what happens when you are honest. Life gets better because you feel good about yourself. But...fewer sore throats and headaches? The improved physical health of the subjects certainly adds to the evidence that persistent stress does real biochemical things to us, and harms our physical as well as our mental health.

In my book and this space I write about The Perception Gap, the harm that arises when, because of the subjective way we assess and respond to risk, we worry too much about some lesser risks and not enough about some bigger ones. Getting risk wrong in either direction can lead to dangerous behaviors. But the worrying-too-much part of The Perception Gap can also trigger all sorts of health damage from stress.

So tell the truth, and try to find ways to reduce how stressed you feel. Neither will be easy. But more and more evidence suggests that both will protect you from the insidious damage of chronic stress, and help you live healthier and even longer lives.